Flow generators are used to generate a flow of breathable gas for treatment of various respiratory conditions. The flow generator may be configured to be connected to a patient interface, for example a mask, to deliver the flow of breathable gas to the patient's airways. The flow generator may also be configured to be connected to a humidifier configured to store a supply of water for humidifying the flow of breathable gas prior to delivery to the patient.
A blower is provided in the flow generator to generate the flow of breathable gas. A blower may comprise a motor comprising a rotating part including, for example, a shaft having an impeller(s) mounted thereon, and a non-rotating part. The operation of the motor may generate noise and vibration. As the therapy may be delivered to the patient during sleep, the generation of noise and vibration may reduce the effectiveness of the therapy.
The flow generator may also include electronics configured to control the operation of the motor of the blower to vary the pressure of the flow of breathable gas that is generated by the blower. The electronics may be damaged by the flow of breathable gas generated by the blower, for example by debris drawn into the flow generator.
A flow sensor may be provided to measure the volume of the flow of breathable gas generated by the blower. Gaps in the flow generator chassis assembly may allow portions of the flow of breathable gas to bypass the flow sensor, thus providing an inaccurate measure of the flow.